This invention relates broadly to devices for holding coiled rope in life raft canisters for allowing easy pay out thereof in times of emergency.
Some life raft storage systems comprise clamshell canisters designed to hold, for example, sixteen man life rafts with provisions for survival at sea in an event of an emergency. Such life rafts are inflated by compressed-air cylinders which are also encased in the clamshell canisters. Compressed air is released from the cylinders into the rafts when lanyards, that are respectively attached to valves of the cylinders, are pulled. In a prior-art example, such a lanyard is attached to an inner-end portion of a 100 ft. coiled rope bundle, which is also encased in the clamshell canister, with an outer-end portion of the coiled rope being attached to a tie cleat on a boat. When an emergency occurs, for example when a boat on which such a clamshell canister is mounted is sinking, the clamshell canister is thrown overboard along with the enclosed life raft and compressed-air cylinder. Since the outer-end portion of the coiled rope is affixed to the cylinder valve, as the clamshell canister, with life raft and cylinder, fall downwardly, the coiled rope is paid out, or pulled out, of the clamshell canister until the clamshell canister travels 100 feet from the tie cleat to which the outer-end portion of the rope is attached. At this point, the rope is placed under tension, which tension pulls the lanyard, thereby opening the valve on the cylinder to release compressed air to inflate the raft in the clamshell canister. As the raft inflates, it applies outwardly directed force on the clamshell canister, which separates top and bottom halve shells of the clamshell canister, thereby releasing the life raft to be ready for use.
Previous methods of storing coiled rope in such clamshell canisters has often caused "snagging" of the rope during payout thereof. That is, while a coiled rope has been paid out of a falling clamshell canister, it has sometimes, snagged, so that it never applied tension on the inner-end portion of the rope and therefore never activated the cylinder of compressed air.
U.S. Pat. No. 5,154,653 to Ketterman et al. describes a bung plug assembly, or painter line assembly, which allows easy payout of rope from a clamshell canister with reduced possibilities of snagging. The bung plug assembly described in that patent comprises a resilient grommet cap holding a tubularly shaped housing to a canister with coiled rope in the tubularly-shaped housing. The bung plug assemble of that patent pays out rope from a coiled rope winding in the tubularly-shaped housing. There is a resilient rear cap at an opposite end of the tubularly-shaped housing through which an inner-end portion of the rope extends to a lanyard attached to a valve of a compressed-air cylinder. A bung plug through which an outer-end portion of the rope extends is insertable into a grommet-cap bore of the grommet cap, and the grommet cap has radially directed slots in which half shell edges of a clamshell canister engage. A resilient molded key engages a key slot of the grommet cap for resilently contacting the clamshell canister and holding the bung plug assembly in position at the intersection of the half shells on the clamshell canister. Rope is paid out through the grommet-cap bore once the bung plug is pulled out of the grommet-cap bore by tension.
Although the apparatus described in U.S. Pat. No. 5,154,653 has been quite successful, it has had several shortcomings. A main problem with that apparatus has been that it could only be mounted at the interface between the half shells of the clamshell canister. This has proven to be disadvantageous in cases where life rafts are unusually large so that the assemblies do not always conveniently fit into the clamshell canisters at the interfaces of the half shells. Also, it has been disadvantageous where tie cleats and clamshell canisters cannot be conveniently aligned for proper deployment.
Stated another way, bung plug assemblies of the prior art have not provided sufficient mounting-position flexibility. Thus, it is an object of this invention to provide a painter line assembly, or bung plug assembly, which can be mounted at almost any position on a clamshell canister.
Another problem with most bung plug assemblies of the prior art is that unauthorized persons could easily tamper with them. For example, in the case of the assembly of U.S. Pat. No. 5,154,653 one could easily remove the resilient molded key and thereby loosen the mount of the bung plug assembly. Accordingly, it is a further object of this invention to provide a painter line assembly which discourages unauthorized tampering.
Still another difficulty with the prior-art bung plug assembly of U.S. Pat. No. 5,154,653 is that, because it must be mounted at the interface of the half shells, the stability of its mount depends upon the relative positions of the half shells. Similarly, it cannot be mounted on the clamshell canister until the half shells are assembled together. Because of this, the bung plug assembly sometimes interfered with closing the half shells to enclose the life raft. Thus, it is yet another object of this invention to provide a painter line assembly which can be stably mounted on half shells of a life-raft clamshell canister before the half shells are brought together so that it does not unduly interfere with assembly of the half shells.